SURESH R CHANDRA, MD
Medical Practice at University Ave, Madison, WI

5652639, Jul 29, 1997

Feb 28, 1996

8/608489

Achyut S. Patel - Glen Arm MD
Suresh R. Chandra - Middleton WI

A61B 310, A61B 300

351205

An indirect ophthalmoscope is designed to provide a properly oriented stereoscopic image of the retina or vitreous of an eye from an inverted image produced by a condensing lens. The ophthalmoscope re-orients the inverted indirect image in the vertical direction using a primary image inverting assembly including two primary reflecting surfaces mounted at right angles for each one of right and left indirect images. The inverted indirect image is re-oriented in the horizontal direction using a secondary image flipping assembly including two secondary reflecting surfaces mounted in a trapezoidal relation for each of the left and right images. The secondary image flipping assembly also splits the images, re-directing the left and right indirect images to right and left eyepieces, respectively, of the ophthalmoscope to provide a true stereoscopic image. The reflecting surfaces employed in the ophthalmoscope are preferably implemented using highly reflective mirrors or as prisms employing total internal reflection. The ophthalmoscope of the present invention includes an illumination unit for providing illumination of the retina-vitreous under observation, and a head strap whereby the ophthalmoscope and illumination unit may be supported on the head of an observer.